Motor having split spray ring for cooling end turns

ABSTRACT

A motor is cooled with a coolant. The motor includes a rotor rotatable about an axis, a stator including a stator core and windings wound about the stator core, a housing enclosing at least a portion of the stator, and a resiliently deflectable spray ring extending circumferentially relative to the axis. The spray ring defines at least one orifice configured to direct coolant on the stator. The spray ring presents first and second arcuately spaced apart ends defining a gap therebetween.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/256,240, filed Sep. 2, 2016, entitled MOTOR HAVING SPLITSPRAY RING FOR COOLING END TURNS, which claims the benefit of andpriority from U.S. Provisional Application No. 62/213,461 filed Sep. 2,2015, entitled MOTOR BEARING LUBRICATION ARRANGEMENT, the entiredisclosure of each of which is hereby incorporated by reference herein.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to a spray ring for providingcoolant to the end turns of a stator.

2. Discussion of the Prior Art

Those of ordinary skill in the art will appreciate that electric motorsconventionally include a stator including a core and windings woundabout the core. Motor operation typically generates heat that isconventionally at least in part dissipated by means of any one or moreof a variety of cooling devices and/or techniques, including but notlimited to cooling jackets, heat sinks, fans, and/or sprays. Forinstance, a coolant might be sprayed onto the windings in order todissipate heat therefrom.

SUMMARY

According to one aspect of the present invention, a motor configured tobe cooled with a coolant is provided. The motor comprises a rotorrotatable about an axis, a stator including a stator core and windingswound about the stator core, a housing enclosing at least a portion ofthe stator, and a spray ring extending circumferentially relative to theaxis. The spray ring defines at least one orifice configured to directcoolant on the stator. The stator core presents an outer circumferentialstator core surface. The housing includes an inner housing surface inpart engaging the stator core surface and in part defining a recessedchannel radially outward relative to the stator core surface. The sprayring overlies the channel and engages the inner housing surface adjacentthe channel, such that the inner housing surface and the spray ringcooperatively define a coolant-directing conduit that extendscircumferentially around at least substantially half of thecircumference of the stator core. The coolant-directing conduit isconfigured to direct coolant to the at least one orifice.

According to another aspect of the present invention, a motor configuredto be cooled with a coolant is provided. The motor comprises a rotorrotatable about an axis, a stator including a stator core and windingswound about the stator core, and a spray ring extendingcircumferentially relative to the axis. The spray ring defines aplurality of orifices configured to direct coolant on the stator. Thespray ring presents first and second arcuately spaced apart endsdefining a gap therebetween. The spray ring presents a middle spacedcircumferentially equally from each of the ends, such that a first sprayring side extends from the first end to the middle and a second sprayring side extends from the second end to the middle. A plurality of theorifices is defined in the first spray ring side. Adjacent ones of theorifices defined in the first spray ring side define an orifice spacingtherebetween. The orifice spacing progressively decreases for at leastsome of the adjacent ones of the orifices defined in the first sprayring side in a direction moving away from the first end and toward themiddle.

According to another aspect of the present invention, a motor configuredto be cooled with a coolant is provided. The motor comprises a rotorrotatable about an axis, a stator including a stator core and windingswound about the stator core, a resiliently deflectable spray ringextending circumferentially relative to the axis, and a ring deflector.The spray ring defines at least one orifice configured to direct coolanton the stator. The spray ring presents first and second arcuately spacedapart ends defining a gap therebetween. The ring deflector is operableto selectively deflect the spray ring and thereby expand or contract thegap. The ring deflector comprises a wedge fitted in the gap. The wedgeis adjustably positionable in a generally radial direction. The wedgeincludes a pair of tapered faces engaging corresponding ones of the endsof the spray ring, such that generally radial shifting of the wedgedeflects the spray ring and results in corresponding expansion orcontraction of the gap.

This summary is provided to introduce a selection of concepts in asimplified form. These concepts are further described below in thedetailed description of the preferred embodiments. This summary is notintended to identify key features or essential features of the claimedsubject matter, nor is it intended to be used to limit the scope of theclaimed subject matter.

Various other aspects and advantages of the present invention will beapparent from the following detailed description of the preferredembodiments and the accompanying drawing figures.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

Preferred embodiments of the present invention are described in detailbelow with reference to the attached drawing figures, wherein:

FIG. 1 is a front perspective view of a motor constructed in accordancewith a preferred embodiment of the present invention;

FIG. 2 is a rear perspective view of the motor of FIG. 1;

FIG. 3 is a rear perspective view of the motor of FIGS. 1 and 2, withthe rear cover removed;

FIG. 4 is an exploded rear perspective fragmented view of the motor asshown in FIG. 3;

FIG. 5 is a fragmentary cross-sectional side view of the motor as shownin FIGS. 3 and 4;

FIG. 6 is a front, bottom perspective view of the motor shell and rearend plate of the motor of FIGS. 1-5;

FIG. 7 is a front, top perspective view of the motor shell and rear endplate as shown in FIG. 6;

FIG. 7a is an enlarged, fragmentary view of a portion of the motor shelland rear end plate as shown in FIG. 7;

FIG. 8 is a cross-sectional side view of the motor of FIGS. 1-5;

FIG. 9 is a cross-sectional front perspective view of the motor of FIGS.1-5 and 8;

FIG. 10 is a cross-sectional rear perspective view of the motor of FIGS.1-5, 8, and 9;

FIG. 11 is a front perspective view of the motor shell, stator, sprayrings, rear end plate, and bearing cap of the motor of FIGS. 1-5 and8-10;

FIG. 12 is an exploded front perspective view of the motor shell,stator, spray rings, rear end plate, and bearing cap of the motor asshown in FIG. 11;

FIG. 13 is an enlarged, rear perspective view of the bearing cap of themotor;

FIG. 14 is a front perspective view of the bearing cap as shown in FIG.13;

FIG. 15 is a front view of the motor shell, rear end plate, spray rings,and bearing cap of FIGS. 1-5 and 8-11;

FIG. 16 is a cross-sectional side view of the motor shell, rear endplate, spray rings, and bearing cap taken along line 16-16 of FIG. 15;

FIG. 17 is an enlarged, fragmentary view of a portion of the motorshell, rear end plate, and rear spray ring taken along line 17-17 ofFIG. 16;

FIG. 18 is an enlarged, fragmentary view of a portion of the motorshell, rear end plate, and rear spray ring taken along line 18-18 ofFIG. 16, particularly illustrating the use of a wedge for deflecting thespray ring and thereby at least in part securing the spray ring;

FIG. 19 is an enlarged, fragmentary cross-sectional front view of aspray ring as shown in FIGS. 1-5, 8-12, and 15-18, particularlyillustrating the orifice spacing along the ring;

FIG. 20 is an enlarged, fragmentary, cross-sectional rear perspectiveview of motor, particularly illustrating end turn cooling and bearinglubrication;

FIG. 21 is an enlarged, fragmentary, top perspective view of the backsof the rear end plate, bearing, and bearing cap, particularlyillustrating the fluid collection chamber;

FIG. 22 is a bottom perspective view of the fronts of the rear endplate, bearing, and bearing cap of FIG. 21;

FIG. 23 is an enlarged, fragmentary, cross-sectional side view of therear end plate, bearing, and bearing cap taken along line 23-23 of FIG.22, in addition to the shaft, and particularly illustrating the flowpath of coolant through the collection chamber, bearing cap, andbearing;

FIG. 24 is a front perspective view of a motor shell, a rear end plate,and a pair of spray rings in accordance with a second embodiment of thepresent invention;

FIG. 25 is an enlarged, fragmentary, cross-sectional view of anadjustable fastener and a corresponding shiftable element for deflectingone of the spray rings of FIG. 24 and thereby at least in part securingthe spray ring;

FIG. 26 is a front, top perspective view of a motor shell and a rear endplate in accordance with a third embodiment of the present invention;

FIG. 27 is a front, bottom perspective view of the motor shell and rearend plate of FIG. 26;

FIG. 28 is a cross-sectional side view of the motor shell and rear endplate of FIGS. 26 and 27, taken along line 28-28 of FIG. 27; and

FIG. 29 is a cross-sectional side view of the motor shell and rear endplate of FIGS. 26-28, taken along line 29-29 of FIG. 27.

The drawing figures do not limit the present invention to the specificembodiments disclosed and described herein. The drawings are notnecessarily to scale, emphasis instead being placed upon clearlyillustrating the principles of the preferred embodiments.

Furthermore, directional references (e.g., top, bottom, front, back,side, etc.) are used herein solely for the sake of convenience andshould be understood only in relation to each other. For instance, acomponent might in practice be oriented such that faces referred to as“top” and “bottom” are sideways, angled, inverted, etc. relative to thechosen frame of reference.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is susceptible of embodiment in many differentforms. While the drawings illustrate, and the specification describes,certain preferred embodiments of the invention, it is to be understoodthat such disclosure is by way of example only. There is no intent tolimit the principles of the present invention to the particulardisclosed embodiments.

Motor Overview

With initial reference to FIGS. 1 and 2, an electric motor 10 isprovided for use in a machine or appliance (not shown). Moreparticularly, the motor 10 is preferably a traction motor used to propela vehicle, such as a construction or agricultural self-propelledvehicle, although use of the motor in an alternative machine and/orapplication is permissible.

As best shown in FIGS. 8-10, the motor 10 broadly includes a rotor 12and a stator 14. The rotor 12 is rotatable about an axis. In a preferredembodiment, as shown, the stator 14 at least substantially circumscribesthe rotor 12, such that the motor 10 is an inner rotor motor. It ispermissible according to some aspects of the present invention, however,for the motor to be an outer rotor motor or a dual rotor motor.

As will be discussed in greater detail below, the rotor 12 preferablyincludes a rotor core 16, a plurality of magnets 18, and a shaftassembly 20 defining a rotational axis for the rotor. In the preferredtraction motor embodiment, the shaft assembly 20 is directly orindirectly coupled to one or more wheels (not shown) of the vehicle(also not shown).

As will also be discussed in greater detail below, the stator 14preferably includes a stator core 22, an electrically insulativecovering (not shown) on at least a portion of the stator core 22, and aplurality of windings or coils 24 (shown only schematically) wound aboutthe stator core 22.

The rotor 12 and the stator 14 preferably define a thin,circumferentially extending gap 26 therebetween.

The motor 10 further preferably includes a housing 28. The housing 28preferably includes a shell 30, a front end plate 32, and a rear endplate 34. The shell 30 and the front and rear end plates 32 and 34,respectively, preferably present a motor chamber 36 that at leastsubstantially receives the stator 14 and the rotor 12.

In a preferred embodiment, the shell 30 extends generallycircumferentially about the stator 14 to present an inner surface 38that in part defines the motor chamber 36. It is permissible accordingto some aspects of the present invention, however, for the shell toextend in such a manner as to provide one or more flat sides, incontrast to the preferred generally cylindrical form, or to be otherwisealternatively shaped.

The shell 30 preferably extends generously continuously, such that themotor 10 is a closed motor. However, it is permissible according to someaspects of the present invention for the shell to include openings orslots therethrough. For instance, openings or slots may be provided forcooling, power and sensor connectiveness, and/or access purposes.

The front and rear end plates 32 and 34 preferably support respectivefront and rear bearing assemblies 40 and 42 that, in a broad sense,rotatably support the shaft assembly 20 and, in turn, the rotor 12.Alternative or additional bearing assembly supports or shaft assemblysupports may be provided without departing from the scope of the presentinvention, however.

The front end plate 32 is preferably secured to the shell 30 via aplurality of fasteners (not shown). In contrast, the rear end plate 34is preferably integrally formed with the shell 30. For instance, therear end plate 34 and the shell 30 may suitably be formed during asingle casting process. However, it is permissible according to someaspects of the present invention for the end plates and the shell to beinterconnected by any means known in the art, including but not limitedto integral interconnection or the use of fasteners, latches, pressfits, and/or adhesives.

In a preferred embodiment, as illustrated, the end plates 32 and 34define respective central openings 44 and 46 therethrough. Exclusive ofsuch openings 44 and 46, however, the end plates 32 and 34 arepreferably at least substantially solid in construction, such thatingress of contaminants therethrough is at least generally prohibited.It is permissible according to some aspects of the present invention,however, for either or both of the end plates to define cooling, powerand sensor, and/or other types of openings therethrough.

The shell 30 and the end plates 32 and 34 preferably comprise aluminum,although other materials may be used without departing from the scope ofsome aspects of the present invention.

The shell 30 and the end plates 32 and 34 will be described in greaterdetail below.

Preferably, the motor 10 further includes an end cover 48 secured to therear end plate 34. The cover 48 provides additional protection againstingress of contaminants into the motor chamber 36 and onto an exposedportion 50 of the rotor 12 that extends out of the motor chamber 36through the rear end plate 34.

Yet further, the motor 10 includes a plurality of control componentsbroadly denoted by reference numeral 52. Control components 52 may be ofany type or configuration required for the particular motor application.

Stator

As noted previously, the stator 14 preferably includes the stator core22, an electrically insulative covering (not shown) on at least part ofthe stator core 22, and the plurality of windings or coils 24 woundabout the stator core 22.

In a preferred embodiment, the stator 14 is generally toroidal in form.The stator core 22 is likewise preferably generally toroidal in form anddefines an axis of the stator 14. Preferably, the axis of the stator 14is coaxial with that of the rotor 12. However, it is permissibleaccording to some aspects of the present invention for the axes to benon-coaxial.

The stator core 22 is preferably a laminated stator core comprising aplurality of axially stacked laminations (not shown). However, it ispermissible for the stator core to be a solid stator core withoutdeparting from the scope of the present invention.

The stator core 22 preferably comprises steel. However, it ispermissible without departing from the scope of the present inventionfor any one or more of a variety of suitable materials to be used forthe stator core.

As best shown in FIGS. 11 and 12, the stator core 22 preferably presentsa radially inner circumferential surface 54 defining an inner corediameter and a radially outer circumferential surface 56 defining anouter core diameter. Furthermore, the stator core 22 preferably presentsa pair of opposite, axially spaced apart front and rear end faces 58 and60 defining corresponding front and rear axial margins or ends 62 and 64of the stator core. The end faces 58 and 60 are preferably at leastsubstantially planar and parallel with each other, although non-paralleland/or non-planar surfaces are permissible according to some aspects ofthe present invention.

The stator core 22 preferably includes an annular yoke 66 and, as bestshown in FIGS. 11 and 12, a plurality of arcuately spaced apart teeth 68extending at least generally radially from the yoke 66. Each pair ofadjacent teeth 68 preferably defines a slot 70 therebetween. Preferably,in keeping with the preferred inner rotor motor design, the teeth 68extend radially inwardly from the yoke 66, although it is permissibleaccording to some aspects of the present invention for the teeth toextend generally outwardly (e.g., in the case of an outer rotor motor).Each tooth 68 preferably includes a generally radially extending arm(not shown) and a generally arcuately extending crown 72 extending fromone end of the arm. Each crown 72 preferably presents a circumferentialcrown face 74 spaced opposite the yoke 66. The circumferential crownfaces 74 preferably cooperatively define the inner circumferentialsurface 54 of the stator core 22. The inner circumferential surface 54of the stator core 22 is thus preferably discontinuous.

As noted previously, although the above-described inner rotor motordesign is preferred, it is permissible according to some aspects of thepresent invention for the motor to alternatively be an outer rotormotor. In such an alternative embodiment, the teeth would instead extendgenerally radially outwardly from yoke, with the crown faces thereforecooperatively defining a discontinuous outer circumferential surface ofthe stator core. In an alternative dual rotor motor design, teeth wouldextend both generally radially inwardly and generally radially outwardlyfrom the yoke, with both the inner and outer circumferential surfaces ofthe stator core being discontinuous.

The coils 24 preferably comprise electrically conductive wiring 76 woundabout the stator core 22. The wiring 76 is preferably wound about eachof the teeth 68 through the slots 70 to form the coils 24, with each ofthe coils 24 corresponding to one of the teeth 68. More particularly,the wiring 76 is preferably wound about each arm so as to encircle thearm and form the coils 24. The coils 24 each thus extend in part pastthe axial ends 62 and 64 of the stator core 22. More particularly, eachcoil 27 presents front and rear end turns 78 and 80, respectively,positioned adjacent respective ones of the ends 62 and 64 of the statorcore 22.

Preferably, each coil 24 presents a radially innermost side 82, aradially outermost side 84, and a pair of axially spaced apart front andrear endmost sides 86 and 88. Each innermost side 82 preferably includesa pair of axially spaced apart frontmost and rearmost regions 82 a and82 b. Similarly, each outermost side 84 preferably includes a pair ofaxially spaced apart frontmost and rearmost regions 84 a and 84 b. Thefront endmost side 86 extends between and interconnects the frontmostregions 82 a and 84 a such that the front endmost side 86 and thefrontmost regions 82 a and 84 a cooperatively form the front end turn78. Similarly, the rear endmost side 88 extends between andinterconnects the rearmost regions 82 b and 84 b such that the rearendmost side 88 and the rearmost regions 82 b and 84 b cooperativelyform the rear end turn 80.

The wiring 76 preferably comprises copper, although aluminum or any oneor more of a variety of electrically conductive materials may be usedwithout departing from the scope of the present invention.

The wiring 76 is preferably wound in such a manner that the motor 10 isa three (3) phase motor. Alternative phasing is permissible within thescope of the present invention, however.

As noted previously, an insulative covering (not shown) is preferablyprovided on the stator core 22. The covering preferably comprises an atleast substantially electrically insulative material. For instance, thecovering may comprise a synthetic resin material. However, any one ormore of a variety of substantially electrically insulative materials maybe used without departing from the scope of the present invention.Furthermore, use of any one or more of a variety of insulation means,including but not limited to the use of electrically insulativeovermolding, powder-coating, inserts, and/or liners, is permissibleaccording to some aspects of the present invention. It is alsopermissible according to some aspects of the present invention for thestator core to be devoid of electrical insulation. The insulativecovering preferably covers only part of the core. For example, it isoften common for the crown face 74 of each tooth 68 to be exposed (i.e.,devoid of the insulative covering). It is permissible, however, for thecovering to fully encapsulate the stator core according to certainaspects of the present invention.

Rotor

As briefly discussed above, the rotor 12 preferably includes the rotorcore 16, the plurality of magnets 18, and the shaft assembly 20.

In more detail, as best shown in FIGS. 8-10, the shaft assembly 20preferably includes an inner hub 90, an outer support ring 92, aconnecting plate 94 extending between and interconnecting the hub 90 andthe support ring 92, and a shaft 96 including a connection end 100.

The hub 90 and the shaft 96 may be integrally formed, as illustrated.Alternatively, the hub and shaft may be discrete componentsinterconnected to each other in any suitable manner such that rotationof the hub and the shaft occurs simultaneously. For instance, the hubmight be at least in part tubular so as to define a hub opening thatreceives a discrete shaft and fixes the shaft relative to the hub, suchthat the shaft and the hub rotate in concert.

The hub 90 preferably includes a front end 104 and a rear end 106. Therear end 106 of the hub 90 preferably extends through the opening 46 inthe rear end plate 34, while the shaft 96 and the front end 104 of thehub 90 preferably extends through the opening 44 in the front end plate32.

The hub 90, the connecting plate 94, and the support ring 92 arepreferably integrally formed. More particularly, the hub 90, theconnecting plate 94, and the support ring 92 are preferably formed ofcast iron via a single casting process. It is permissible according tosome aspects of the present invention, however, for the hub, theconnecting plate, and/or the support ring to comprise any one or more ofa variety of materials. For instance, aluminum or a high-strengthsynthetic resin might be used. Furthermore, it is permissible accordingto some aspects of the present invention for the hub, the connectingplate, and/or the support ring to be discrete components interconnectedby any means known in the art, including but not limited to fasteners,latches, and/or adhesives.

Preferably, the rotor core 16 circumscribes and is supported on the hub90. The magnets 18 are preferably permanent magnets embedded in orotherwise fixed relative to (e.g., via adhesives or glues) the rotorcore 16. It is permissible according to some aspects of the presentinvention, however, for alternative rotor configurations to be used. Forinstance, the rotor could alternatively include a plurality of polesegments alternately arcuately arranged with a corresponding pluralityof permanent magnets.

Motor Shell and Spray Ring Assemblies

As noted previously, the motor shell 30 preferably extends generallycircumferentially about the stator 14. Furthermore, the shell 30preferably cooperates with the front and rear end plates 32 and 34,respectively, to present the motor chamber 36. More particularly, theshell 30 preferably defines the inner surface 38 that in part definesthe motor chamber 36.

In a preferred embodiment, the outer circumferential surface 56 of thestator core 22 includes an interface region 108. The inner surface 38 ofthe shell 30 preferably includes a corresponding interface portion 110that directly engages (i.e., abuts) the interface region 108 of thestator core 22.

The inner surface 38 of the shell 30 further preferably includes acoolant-routing portion 112 adjacent the interface portion 110. Thecoolant-routing portion 112 is preferably recessed relative to theinterface portion 110, although non-recessed embodiments are permissibleaccording to some aspects of the present invention.

The coolant-routing portion 112 is preferably opposed to and generallyspaced from a corresponding coolant-routing region 114 defined along theouter circumferential surface 56 of the stator core 22 and adjacent theinterface region 108. The coolant-routing region 114 is preferably notrecessed relative to the interface region 108, although recessedembodiments are permissible according to some aspects of the presentinvention.

The coolant-routing portion 112 and the coolant-routing region 114preferably cooperatively define a stator-cooling passage 116 thatdefines a portion of a larger flow path 118 for a coolant. (Otherportions of the flow path 118 will be described in detail below).Preferably, flow of a coolant through the stator-cooling passage 116along the flow path 118 enables dissipation of heat associated withoperation of the motor 10.

Although it is preferred that the stator-cooling passage 116 is formedby a recessed coolant-routing portion 112 and a non-recessedcoolant-routing region 114, as described above, alternativeconfigurations are permissible. For instance, the coolant-routingportion might be non-recessed, while the coolant-routing region isrecessed; both the coolant-routing portion and the coolant-routingregion might be recessed; or the coolant-routing portion and thecoolant-routing region might be alternately recessed and non-recessed incoordination with each other so as to define a three-dimensionalstator-cooling passage.

The coolant may be any fluid known in the art. For instance, the coolantmight be a liquid such as water or a gas such as air. The coolant mightalso comprise a plurality of solid particles that collectively behave ina generally fluid-like manner (e.g., via flowing). Furthermore, as willbe discussed in greater detail below, the coolant is preferablyadditionally be operable as a lubricant (e.g., for the front and rearbearing assemblies 40 and 42, respectively). Most preferably, thecoolant comprises oil.

The stator-cooling passage 116 is preferably generally tortuous in formso as to increase the distance traveled by coolant flowing therethroughand therefore increase the heat-absorption and/or -dissipation effectshad by the coolant. In a preferred embodiment, as illustrated, forinstance, the stator-cooling passage 116 includes a plurality of fluidlyinterconnected, generally S-shaped portions. More particularly, thestator-cooling passage 116 preferably comprises a plurality ofcircumferentially spaced apart, generally straight, generally axiallyextending lateral portions 120 interconnected by axially spaced part,generally curved, generally circumferentially extending turns 122. Theturns 122 redirect the flow such that a coolant in the stator-coolingpassage 116 flows in an opposite direction in each adjacent lateralportion 120. Preferably, a plurality of turns 122 are provided such thatthe coolant changes direction multiple times along the flow path 118.

Although the above-described curved, S-shaped configuration ispreferred, it is permissible according to some aspects of the presentinvention for the stator-cooling passage to be alternatively shaped. Thepassage could, for instance, take an angularly zig-zagged form, comprisecircumferentially spaced apart sets of axially oriented S-shapedsegments, include square turns rather than the illustrated curved turns,comprise one or more circumferentially extending helical spirals, etc.In addition, the motor may alternatively be provided with multiplediscrete cooling passages rather than just the single passage shown.

Preferably, the stator-cooling passage 116 is generally regular in itsconfiguration (e.g., equal and/or repeatable spacing between lateralportions 120, constant axial span, general symmetry, etc.). Irregularpassages are permissible according to some aspects of the presentinvention, however,

Preferably, the stator-cooling passage 116 is axially centered betweenthe ends 62 and 64 of the stator core 22. Non-centered (i.e., offset)configurations are permissible according to some aspects of the presentinvention, however.

Furthermore, in keeping with the desired heat-dissipation functionality,it is also preferred that the stator-cooling passage 116 spans at leasta substantial axial portion of the stator core 22 between the front andrear ends 62 and 64, respectively. More particularly, in a preferredembodiment, the stator-cooling passage 116 presents front and rearmargins 124 and 126, respectively, spaced apart an axial distance suchthat the stator-cooling passage 116 spans at least half the axial lengthof the stator core 22 (wherein the axial length of the stator core isunderstood to be an axial distance between the front and rear ends 62and 64). More preferably, the stator-cooling passage 116 spans at leasttwo thirds of the axial length of the stator core 22. Most preferably,the stator-cooling passage 116 spans about three quarters or more of theaxial length of the stator core. Lesser axial spans are permissibleaccording to some aspects of the present invention, however.

Additional features configured to influence flow through thestator-cooling passage 116 may also be provided. For instance,turbulence-generating flow disruptors (not shown) might extend into theflow path.

Preferably, the housing 28 defines a coolant inlet 128, best shown inFIGS. 6 and 7, through which coolant enters the stator-cooling passage116. The inlet 128 is preferably centered between the front and rearmargins 124 and 126 of the stator-cooling passage 116, although offsetconfigurations are permissible according to some aspects of the presentinvention.

Coolant entering the stator-cooling passage 116 through the inlet 128preferably flows in part in a first circumferential direction through afirst branch 130 of the stator-cooling passage 116 and in part in asecond circumferential direction through a second branch 132 of thestator-cooling passage 116. That is, the flow path 118 is unitary at theinlet 128 but thereafter diverges in circumferentially oppositedirections such that the coolant flows about opposite sides of thestator core 22. This configuration minimizes stress conditions in andadjacent the coolant inlet 128 that occur due to interference betweenthe stator core 22 and the shell 30 (more particularly, between theinterface region 108 of the outer circumferential surface 56 of thestator core 22 and the interface portion 110 of the inner surface 38 ofthe shell 30). Such a configuration is particularly advantageous in apreferred embodiment in which a significant degree of interference isrequired between the core 22 and the shell 30 at lower temperatures tomaintain interference at high temperatures (e.g., when the shell 30comprises aluminum and the stator core 22 comprises steel).

The shell 30 and the stator core 22 further cooperatively definecollection areas 134 and 136 downstream of and fluidly interconnectedwith the portions of the flow path 118 defined by respective ones of thebranches 130 and 132. More particularly, the collection areas 134 and136 are preferably positioned generally adjacent each other andgenerally diametrically opposed to the inlet 128. Coolant must thereforeflow through the inlet 128 and around at least substantially half thecircumference of the stator core 22 through one of the branches 130 or132 of the stator-cooling passage 116 to reach the corresponding one ofthe collection areas 134 and 136.

Similar to the stator-cooling passage 116, the collection areas 134 and136 are preferably cooperatively defined by the coolant-routing portion112 of the shell 30 and the coolant-routing region 114 of the statorcore 22. As discussed above with respect to the stator-cooling passage116, however, alternative means of defining the collection areas arealso permissible.

The shell 30 further in part defines a pair of coolant-directingconduits 138 and 140 downstream of and fluidly interconnected withcorresponding ones of the collection areas 134 and 136. Moreparticularly, as will be described in greater detail below, the motor 10preferably includes a pair of axially spaced apart spray ring assemblies142 and 144 that cooperate with the coolant-routing portion 112 of theshell 30 to define respective ones of the conduits 138 and 140.

As best shown in FIGS. 11, 12, 16, and 18, each spray ring assembly142,144 comprises a respective spray ring 146,148 and a correspondingrespective ring deflector 150,152. Each spray ring 146 and 148 at leastsubstantially overlies a corresponding portion of the coolant-routingportion 112 to cooperatively define a corresponding one of thecoolant-directing conduits 138 and 140.

The spray ring 146 extends generally arcuately and presents first andsecond arcuately spaced apart ends 154 and 156 defining an arcuate gap158 therebetween. Similarly, the spray ring 148 extends generallyarcuately and presents first and second arcuately spaced apart ends 160and 162 defining an arcuate gap 164 therebetween.

Each spray ring 146,148 preferably comprises a resiliently deformablematerial or materials (e.g., stainless steel) and is expandable orcontractible via modification of the size of the respective gap 158 or164. Such expandability and contractibility enables simplified assemblyand disassembly of the motor 10 and, particularly, the placement of thespray ring assemblies 142 and 144.

Furthermore, such expandability and contractibility allows forsufficient pressure to be developed between the outer faces 172 and 176of the spray rings 146 and 148, respectively, and the inner surface 38of the shell 30 to seal corresponding ones of the coolant-directingconduits 138 and 140, thereby at least substantially preventing coolantleakage.

Preferably, each spray ring 146,148 defines a corresponding plurality oforifices 166 or 168 therethrough. As best shown in FIGS. 11 and 16-19,the orifices 166 and the orifices 168 are preferably arcuately spacedapart, positioned in alignment with each other, and slightly outwardlyoffset (in an axial direction relative to the motor 10 as a whole) froman arcuately extending centerline of the corresponding spray ring 146 or148. It is permissible according to some aspects of the presentinvention, however, for the orifices to be alternatively arranged. Theorifices might be provided in a grid format or randomly placed, forinstance, or they might be aligned with one another and centered alongthe centerline of the spray ring. Preferably, as will be discussed ingreater detail below, the orifices are configured in such a manner as tooptimize or at least substantially optimize the cooling of the stator.

More particularly, coolant preferably flows through the inlet 128 andaround at least substantially half the circumference of the stator core22 through one of the branches 130 or 132 of the stator-cooling passage116 to reach the corresponding one of the collection areas 134 and 136.Then, aided by fluid pressure, coolant from the collection areas 134 and136 flows generally upwardly along the flow path 118 throughcorresponding ones of the coolant-directing conduits 138 and 140.Concurrent with this upward flow, portions of the coolant are releasedthrough the orifices 166 and 168, respectively. Preferably, the orifices166 and 168 are positioned and oriented such that coolant releasedtherethrough is directed onto the stator 14. More particularly, theorifices 166 and 168 preferably spray coolant on the end turns 78 and 80of the coils 24 of the stator 14. Still more particularly, the orifices166 and 168 preferably spray coolant on the frontmost and rearmostregions 84 a and 84 b of the outermost side 84 of each coil 24.

As best shown in FIG. 19 with regard to the spray ring 146 and asdiscussed in more detail below, the orifices 166 and 168 are preferablyunevenly spaced apart in a circumferential direction. More particularly,an initial close spacing adjacent the ends 154,156 or 160,162,respectively, gives way to a larger spacing which then decreases towardthe middle of the corresponding spray ring 146 or 148. For instance, asshown in FIG. 19, it is preferred that an initial close spacing of fivedegrees (5°) gives way to a larger spacing of nineteen degrees (19°),which then decreases to eighteen degrees (18°) and finally fifteendegrees (15°) at the midsection of the spray ring 146 or 148.

The aforementioned variable spacing of the orifices 166 and 168 is suchthat both the fluid pressure in the coolant-directing conduits 138 and140 and fluid pressure through the orifices 166 and 168 is maintained toacceptable levels. That is, it is preferable for sufficient fluidpressure to be maintained in the coolant-directing conduits 138 and 140to ensure coolant reaches around the entirety of the conduits 128 and140, and sufficient pressure through the orifices is necessary to ensurecoolant is directed with enough force to reach desired portions of thestator 14 when countered by forces such as gravity.

It is noted that the sizes and shapes of the orifices (though preferablycircular and identical to one another, as illustrated) may additionallyor alternatively be varied to influence the fluid pressure in thecoolant-directing conduits and through the orifices.

Furthermore, the preferred variable spacing of the orifices 166 and 168is such that the coolant is directed, flows, or falls onto appropriateportions for the stator 14 (e.g, the end turns 78 and 80, as discussedabove). For instance, whereas coolant from upper ones of the orifices166 and 168 might fall or flow from the uppermost ones of the end turns78 and 80 onto intermediately positioned ones of the end turns 78 and80, such coolant might be prevented from reaching the lowermost ones ofthe end turns 78 and 80 due to intervening structure (including othercoils 24). However, the most closely spaced of the orifices 166 and 168(located adjacent the ends 154,156 or 160,162, respectively) arepositioned so as to aim coolant directly at the lowermost ones of theend turns 78 and 80 and with sufficient pressure to overcome orcounterbalance any misdirection (i.e., drooping) associated withgravity. Positioning might also be guided at least in part by thepresence of intervening structures or structure non in need of cooling,including by not limited to insulative structures associated with thecoils 24.

Thus, in summary, the orifices 166 and 168 are preferably configured interms of size, shape, spacing, general arrangement, etc. to in a broadsense optimize coolant flow onto the coils 24.

In a preferred embodiment, each spray ring 146,148 presents a constant,generally rectangular cross-section along its length, such that thespray ring 146 presents smooth, parallel inner and outer faces 170 and172, and the spray ring 148 presents smooth, parallel inner and outerfaces 174 and 176. Furthermore, each spray ring 146,148 preferablyextends circumferentially in such a manner as to form an arc of acircle. The orifices 166 and 168 preferably extend at leastsubstantially orthogonally relative to the immediately adjacent portionsof the respective inner and outer faces 170,172 and 174,176 (i.e., atleast substantially radially relative to the axis of rotation of themotor 10).

It is permissible according to some aspects of the present invention forcoolant to be released onto additional and/or alternative portions ofthe coils as a results of alternative configurations of the spray rings,orifices, and/or other motor components in general.

Coolant sprayed onto the coils 24 thereafter deflects off of the coils24. A portion of the deflected coolant preferably falls under theinfluence of gravity into a drainage collection area 178 defined by theshell 30 and is thereafter drained out of the motor chamber 36 in anysuitable manner known in the art. Preferably, the drained coolant isdirected to a recirculating system that cools and then pumps the coolantback to the motor. Some of the deflected coolant, however, falls into oris directed into the rear bearing assembly 42, where the coolant is theoperable to lubricate and cool components of the rear bearing assembly42, in a manner described in greater detail below.

Thus, in summary, a given supply of coolant first dissipates heat fromthe stator core 22 via travel through the stator-cooling passage 116,next dissipates heat from the end turns 122 of the coils 24 after beingsprayed thereon through the respective orifices 166,168 of the sprayrings 146,148, and finally cools and lubricates components of the rearbearing assembly 42.

Although circularly extending spray rings 146 and 148 positionedradially outside the stator 14 and the rotor 12 so as to circumscribethe stator 14 and the rotor 12 are preferred, it is also permissibleaccording to some aspects of the present invention for the spray ringsto extend circumferentially in a non-circular manner and/or for thespray rings to be positioned radially inside the stator and/or rotor(e.g., as would be the case for an outer rotor motor embodiment).

As noted previously, each spray ring 146 and 148 is expandable orcontractible via modification of the size of the corresponding gap 158or 164. As also noted previously, each spray ring assembly 142,144comprises a spray ring 146 or 148, respectively, and a respective ringdeflector 150 or 152. The ring deflectors 150 and 152 are operable toselectively deflect (i.e., expand or contract) the corresponding sprayring 146,148 to thereby expand or contract the corresponding gap158,164. As will be apparent to one of ordinary skill in the art,expansion of the gap 158 or 164 and, in turn, the spray ring 146 or 148,is desirable to achieve a secure fit in the preferred embodiment, inwhich the spray rings 146 and 148 each circumscribe the rotor 12 and thestator 14. In contrast, contraction of the gap to contract the sprayring is desirable in certain alternative embodiments in which the sprayrings are secured to a circumferentially smaller structure (e.g., incertain outer rotor motor embodiments).

In a preferred embodiment and as shown in FIG. 18 and others, the ringdeflectors 150,152, each preferably include a respective shiftableelement 180 or 182. The shiftable elements 180 and 182 each comprise arespective wedge 184 or 186, in addition to an adjustable threadedfastener 188 or 190. Each wedge 184,186 is preferably adjustablypositionable in a generally radial direction such that generally radialshifting of the wedge 184 or 186 deflects the corresponding one of thespray rings 146,148 and results in corresponding expansion orcontraction of the gap 158 or 164.

More particularly, each wedge 184,186 preferably includes a pair oftapered faces 184 a,184 b and 186 a,186 b, respectively. The faces 184a,184 b and 186 a,186 b preferably engage corresponding ones of the ends154,156 and 160,162 of the spray rings 146 and 148, such that generallyradial shifting of the each wedge 184,186 deflects the correspondingends 154,156 and 160,162 and causes expansion or permits contraction ofthe gap 158 or 164 as described above. Such radial shifting ispreferably driven by the corresponding fastener 188 or 190, whichthreadably engages the wedge 184 or 186 such that rotation of thefastener 188 or 190 results in the generally radial shifting of thewedge 184 or 186.

More particularly, rotation of the fastener 188 or 190 such that thewedge 184 or 186 shifts radially outwardly (i.e., threading of thefastener 188 or 190) results in expansion of the corresponding one ofthe rings 146 and 148. In contrast, rotation of the fastener 188 or 190such that the wedge 184 or 186 shifts radially inwardly permits orenables the corresponding one of the rings 146 and 148 to contract(preferably as a result of its resilient nature and consequent returnfrom the expanded state).

As best shown in FIG. 18, the ends 154,156 and 160,162 of the sprayrings 146 and 148, respectively, preferably include respective chamferedcorners 154 a,156 a and 160 a,162 a angularly corresponding to thetapered faces 184 a,184 b and 186 a,186 b. Provision of the chamferedcorners 154 a,156 a and 160 a,162 a enables a greater contact area toexist between each wedge 184 and 186 and the corresponding ends 154,156and 160,162.

Although the above-described wedge-based deflector 150,152 is preferred,it is permissible according to some aspects of the present invention foralternative ring deflectors to be provided.

For instance, a second preferred pair of spray ring assemblies 310,312and a second preferred motor shell 314 are shown in FIGS. 24 and 25. Itis initially noted that, with certain exceptions to be discussed indetail below, many of the elements of the spray ring assemblies 310,312and the motor shell 314 of the second embodiment are the same as or verysimilar to those described in detail above in relation the spray ringassemblies 142,144 and the motor shell 30 of the first embodiment.Therefore, for the sake of brevity and clarity, redundant descriptionsand numbering will be generally avoided here. Unless otherwisespecified, the detailed descriptions of the elements presented abovewith respect to the first embodiment should therefore be understood toapply at least generally to the second embodiment, as well. It isparticularly noted that the second embodiment may be provided withlubricant collection and distribution means that are similar to thoseassociated with the rear bearing assembly 42 of the first preferredembodiment, despite an alternative configuration being illustrated inFIG. 24.

Similarly to the motor shell 30 of the first preferred embodiment, themotor shell 314 of the second preferred embodiment defines astator-cooling passage 316 for directing coolant flow about a statorcore (not shown). The motor shell 314 further preferably defines a pairof collection areas 318 and 319 downstream of and fluidly interconnectedwith the stator-cooling passage 316. Yet further, the motor shell 314also similarly defines a pair of coolant-directing conduits 320,322.

Similarly to the spray ring assemblies 142,144 of the first preferredembodiment, the spray ring assemblies 310,312 of the second preferredembodiment preferably each include a respective spray ring 324,326 and arespective ring deflector 328,330. Each of the spray rings 324,326includes a respective pair of ends 332,334 or 336,338. Furthermore, eachof the spray rings 324,326 defines a respective gap 340 or 342 betweenthe end pairs 332,334 and 336,338, respectively.

However, in contrast to the ring deflectors 150,152 of the firstpreferred embodiment, the ring deflectors 328,330 of the secondpreferred embodiment preferably each include a pair of shiftableelements 344,346 or 348,350 and a corresponding pair of adjustablefasteners 352,354 or 356,358. Each of the shiftable elements344,346,348,350 preferably comprises a respective plate 360,362,364,366received at least in part within the corresponding gap 340 or 342. Eachfastener 352,354,356,358 preferably comprises a respective screw (e.g.,screw 368 in FIG. 25) and a corresponding threadably interconnected nut(e.g., nut 370 in FIG. 25). The plates 360,362,364,366 preferably engagecorresponding ones of the ends 332,334,336,338 of the correspondingspray rings 146,148, such that generally circumferential (i.e.,generally lateral/tangential) shifting of the plates 360,362,364,366deflects the corresponding ends 332,334,336,338 and causes expansion orpermits contraction of the gaps 340,342.

More particularly, each plate 360,362,364,366 preferably includes arespective pair of generally orthogonally oriented sidewalls (e.g.,sidewalls 366 a,366 b of FIG. 25), each of which is interconnected by acorresponding generally circularly extending rounded portion (e.g.,rounded portion 366 c of FIG. 25). The sidewalls are configured toengage respective ones of the ends 332,334,336,338. Furthermore, thesidewalls cooperate with the corresponding rounded portions to definerespective elongated fastener-receiving slots (e.g., slot 366 d of FIG.25) therethrough.

Each nut is preferably generally cylindrical in form so as to present acircular cross-section. More particularly, each nut presents an outerrounded surface (e.g., surface 370 a in FIG. 25) that engages thecorresponding one of the plates 360,362,364,366 and, more particularly,engages primarily the rounded portion of the corresponding plate (e.g.,rounded portion 366 c of plate 366 in FIG. 25). Such shaping ensures alarge contact area between each nut 376,378,380,382 and thecorresponding plate 360,362,364,366.

Rotation of each screw (e.g., screw 368 of FIG. 25) relative to thecorresponding nut (e.g., nut 370 of FIG. 25) results in shifting of thecorresponding plate 360,362,364,366 along the corresponding fastener(e.g., plate 366 along fastener 358 of FIG. 25).

Provision of the elongated fastener-receiving slots (e.g., slot 366 d ofFIG. 25) facilitates rotation or sliding of each corresponding plate360, 362, 364, and 366 about the corresponding nut (i.e., generallyabout the cylindrical axis thereof) such that the portion of eachsidewall (e.g., sidewalls 366 a,b of FIG. 25) that engages thecorresponding end 332, 334, 336, or 338 of the spray ring 146 or 148varies with the aforementioned generally transverse or circumferentialshifting of the corresponding plate 360, 362, 364, and 366.

It is noted that, while features of the shiftable elements344,346,348,350 are described above and illustrated in the figures,certain of these features are not directly identified in the figures.That is, some features are directly identified only in FIG. 25 and thusonly with respect to the shiftable element 350. However, the othershiftable elements (i.e., the shiftable elements 344,346,348) arepreferably similarly configured.

Also, similarly to the shell 30 of the first preferred embodiment, theshell 314 of the second preferred embodiment defines a drainagecollection area 372 from which lubricant is drained out of the motorchamber in any suitable manner known in the art.

A third preferred motor shell 410 is shown in FIGS. 26-29. It isinitially noted that, with certain exceptions to be discussed in detailbelow, many of the elements of the motor shell 410 of the thirdembodiment are the same as or very similar to those described in detailabove in relation to the motor shell 30 of the first embodiment and/orthe motor shell 314 of the second embodiment. Therefore, for the sake ofbrevity and clarity, redundant descriptions and numbering will begenerally avoided here. Unless otherwise specified, the detaileddescriptions of the elements presented above with respect to the firstand/or second embodiment should therefore be understood to apply atleast generally to the third embodiment, as well. It is particularlynoted that the third embodiment may be provided with lubricantcollection and distribution means that are similar to those associatedwith the rear bearing assembly 42 of the first preferred embodiment,despite an alternative configuration being illustrated in FIGS. 26-29.

Similarly to the motor shell 30 of the first preferred embodiment andthe motor shell 314 of the second preferred embodiment, the motor shell410 of the third preferred embodiment defines a stator-cooling passage412 for directing coolant flow about a stator core (not shown). Themotor shell 410 further preferably defines a pair of collection areas414,416 downstream of and fluidly interconnected with the stator-coolingpassage 412. Yet further, the motor shell 410 also similarly defines apair of coolant-directing conduits 418,420.

Coolant preferably enters the stator-cooling passage 412 via a coolantinlet 422 defined by the shell 410. The inlet 422 preferably comprisesan axially extending conduit defined through a reinforced portion or rib424 of the shell 410.

Preferably, the inlet 422 adjoins the stator-cooling passage 412 at agenerally centered location between front and rear margins 426 and 428,respectively, of the stator-cooling passage 412. Offset configurationsare permissible according to some aspects of the present invention,however.

As described above with respect to the first and second preferredembodiments, the stator-cooling passage 412 of the third preferredembodiment is preferably generally tortuous in form. In a preferredembodiment, for instance, the stator-cooling passage 412 includes aplurality of fluidly interconnected, generally S-shaped portions thatdirect coolant in part in a first generally circumferential directionthrough a first branch 430 of the stator-cooling passage 412 and in partin a second generally circumferential direction through a second branch432 of the stator-cooling passage 412. That is, the flow path of thecoolant is unitary at the inlet 422 but thereafter diverges incircumferentially opposite directions such that the coolant flows aboutopposite sides of the stator core (not shown).

The collection areas 134 and 136 of the first preferred embodimentdirectly connect with the corresponding ones of the coolant-directingconduits 138 and 140. Similarly, the collection areas 318 and 319 of thesecond preferred embodiment directly connect with the corresponding onesof the coolant-directing conduits 320 and 322. In contrast, thecollection areas 414 and 416 of the third preferred embodiment connectwith the corresponding ones of the coolant-directing conduits 418 and420 by means of corresponding transfer channels 434 and 436.

More particularly, enclosed, generally axially extending transferchannels 434 and 436 are defined exclusively by the shell 410 torespectively interconnect collection area 414 with conduit 420 andcollection area 416 with conduit 418. Such a configuration reduces and,most preferably, eliminates the occurrence of leakage during transfer ofcoolant between the collection areas 414,416 and the coolant-directingconduits 418,420. Such a configuration is particularly useful inmaintaining the coolant at a high enough pressure to assuredly propelthe coolant through the coolant-directing conduits 418,420.

Although fully enclosed transfer channels 434 and 436 are preferred, asillustrated, it is permissible for channels fluidly interconnected toone or more peripheral openings (e.g. a slit or a pair of bleed holesfor pressure release as needed) to alternatively be provided.

Similarly to the shell 30 of the first preferred embodiment and theshell 314 of the second preferred embodiment, the shell 410 of the thirdpreferred embodiment further defines a drainage collection area 438 fromwhich coolant or lubricant is drained out of the motor chamber in anysuitable manner known in the art.

Furthermore, excess coolant or lubricant from the transfer channels 434and 436 that does not enter one of the coolant-directing conduits418,420 is drained out of the motor chamber via drainage channels440,442 in fluid communication with corresponding ones of the transferchannels 434 and 436.

Bearing Assemblies

Turning again to the first preferred embodiment and as noted previously,the motor 10 includes front and rear bearing assemblies 40 and 42 thatrotatably support the shaft assembly 20. More particularly, the frontbearing assembly 40 supports the front end 104 of the hub 90, as well asthe shaft 96. The rear bearing assembly 42 supports the rear end 106 ofthe hub 90.

The front bearing assembly 40 preferably comprises a ball bearing 92,although other types of bearing (e.g., roller bearings, sleeve bearings,etc.) may be used as appropriate.

The rear bearing assembly 42 preferably comprises a ball bearing 92 anda lubricant collection structure 192. However, although a ball bearing92 is preferred, it is permissible for other types of bearings (e.g.,roller bearings, sleeve bearings, etc.) to be used as appropriate.

The lubricant collection structure 192 preferably includes a bearing cap194 that secures the bearing 92 relative to the housing 28. Moreparticularly, the housing 28 defines a bearing pocket 196 that at leastsubstantially receives the bearing 92, with the bearing cap 194 at leastin part spanning the bearing pocket 196 and securing the bearing 92therein.

In a preferred embodiment, the bearing cap 194 secures the bearing 92 tothe rear end plate 34 (and within the bearing pocket 196) by means of aplurality of fasteners 198 extending through a corresponding pluralityof fastener-receiving holes 200. Preferably, the fastener-receivingholes 200 extend through corresponding arcuately spaced apart bosses 202forming part of the bearing cap 194 (see, for instance, FIGS. 13 and14). However, alternative or additional securement means (e.g., latchesor adhesives) and arrangements are permissible according to some aspectsof the present invention.

The lubricant collection structure 192 is configured to direct lubricantto the ball bearing 92. More particularly, the lubricant collectionstructure 192 preferably defines a collection chamber 204 configured tocollect lubricant from the motor chamber 36 and direct the lubricant tothe bearing 92. Preferably, the lubricant collection structure 192defines an open top 206 to the collection chamber 204. The open top 206is preferably positioned below some of the windings or coils 24, suchthat lubricant deflected, dripping, etc. from the coils 24 fallsdownwardly from the coils 24 into the collection chamber 204 (i.e., bymeans of gravity). As noted previously, the remaining lubricant falls tothe drainage collection area 178.

In a preferred embodiment, the rear end plate 34 includes a pair ofgenerally radially extending, generally arcuately spaced apart ribs 208and 210 defining a connecting surface 212 therebetween. The bearing cap194 includes a generally radially and arcuately extending flange 214.The flange 214 preferably contacts and extends generally arcuatelybetween the ribs 208 and 210 and is axially spaced from the connectingsurface 212, such that the ribs 208 and 210, the connecting surface 212,and the flange 214 cooperatively at least substantially define thecollection chamber 204. Thus, in the preferred embodiment, the lubricantcollection structure 192 and, more particularly, the collection chamber204, is cooperatively defined by both the bearing cap 194 and a portionof the rear end plate 34 of the housing 28.

In a preferred embodiment, two (2) of the bosses 202 are coextensivewith the flange 214. Distinct bosses are permissible, however.

As best shown in FIG. 20, in which arrows schematically representcoolant flow, the collection chamber 204 preferably receives coolantdeflected off of the end turns 122. The coolant thus is preferablyadditionally functional as a lubricant. The terms “coolant” and“lubricant” as used herein should therefore be understood to be inreference to the same substance. Additional fluid contained in the motorchamber 36 may also be received.

As best shown in FIGS. 15 and 20-23, the lubricant collection structure192 further preferably defines a pair of generally radially extending,arcuately spaced apart lubricant supply passages 216 and 218 in fluidcommunication with the collection chamber 204. As shown schematically bymeans of arrows, lubricant from the collection chamber 204 flows intothe supply passages 216 and 218.

The rear end plate 34 and the bearing cap 194 preferably cooperativelyat least in part define the supply passages 216 and 218. Moreparticularly, the supply passages 216 and 218 are at least in partdefined by the flange 214.

The supply passages 216 and 218 are preferably at least substantiallystraight. It is permissible, however, for curved or meandering supplypassages to be provided.

The lubricant collection structure 192 additionally defines a lubricantinterface area 220 in fluid communication with the supply passages 216and 218 and configured to receive lubricant from the supply passages 216and 218. The interface area 220 preferably abuts the bearing 92 andabuts or nearly abuts the rotor end 98 of the hub 90. The interface area220 is thus configured such that lubricant therein lubricates thebearing 92.

More particularly, the bearing 92 preferably includes an inner race 222and an outer race 224. As shown in FIGS. 10, 16, and others, thelubricant collection structure 192 preferably abuts the outer race 224except at the supply passages 216 and 218 and at exit locations to bediscussed in greater detail below. In contrast, the lubricant collectionstructure 192 is preferably axially spaced from the inner race 222.Thus, coolant may pass through the supply passages 216 and 218 into thelubricant interface area 220 defined between the bearing 92, thelubricant collection structure 192, and the rotor end 98 of the hub 90.

Preferably, the lubricant collection structure 192 defines ahub-receiving opening 226 therethrough. The rotor end 98 of the hub 90preferably extends through the hub-receiving opening 226 and furtherdefines the lubricant interface area 220. Thus, the lubricant interfacearea 220 preferably extends generally circumferentially about the hub90.

In addition, the lubricant collection structure 192 preferably includesa pair of generally radially extending, arcuately spaced apart lubricantdrainage channels 228 and 230 in fluid communication with the interfacearea 220. The drainage channels 228 and 230 are preferably configured todrain lubricant from the interface area 220.

Although a pair of radially extending, arcuately spaced apart drainagechannels 228 and 230 are preferred, it is permissible for analternatively configured drainage channel(s) to be provided. Forinstance, a single channel could be provided for drainage, or aplurality of parallel channels could be provided. Furthermore, althoughthe drainage channels 228 and 230 are preferably at least substantiallystraight, it is permissible according to some aspects of the presentinvention for curved or meandering drainage passages to be provided.

As at least in part indicated by the above structural and functionaldescriptions of the bearing cap 194, the bearing cap 194 is preferablytiered in form. As best shown in FIG. 13, for instance, the bearing cap194 presents a rear face 232 defined by axially spaced outer,intermediate, and inner tiers 234, 236, and 238, respectively. As bestshown in FIG. 14, the bearing cap 194 presents a front face 240 definedby axially spaced apart outside and inside tiers 242 and 244,respectively. Provision of the tiers 242 and 244 and, more particularly,the recessed nature of the inside tier 244 relative to the outside tier242 enables contact to be avoided between the bearing cap 194 and thehub 90. Provision of the outer tier 234 enables a secure fit against theportion of the rear end plate 34 that defines the bearing pocket 196.Provision of the intermediate tier 236 enables a secure fit against boththe aforementioned portion of the rear end plate 34 and the outer race224 of the bearing assembly 42. Provision of the recessed inner tier 238enables formation of the interface area 220.

The preferred forms of the invention described above are to be used asillustration only and should not be utilized in a limiting sense ininterpreting the scope of the present invention. Obvious modificationsto the exemplary embodiments, as hereinabove set forth, could be readilymade by those skilled in the art without departing from the spirit ofthe present invention.

The inventors hereby state their intent to rely on the Doctrine ofEquivalents to determine and access the reasonably fair scope of thepresent invention as pertains to any apparatus not materially departingfrom but outside the literal scope of the invention set forth in thefollowing claims.

What is claimed is:
 1. A motor configured to be cooled with a coolant,said motor comprising: a rotor rotatable about an axis; a statorincluding a stator core and windings wound about the stator core; ahousing enclosing at least a portion of the stator; and a spray ringextending circumferentially relative to the axis, said spray ringdefining at least one orifice configured to direct coolant on thestator, said stator core presenting an outer circumferential stator coresurface, said housing including an inner housing surface in partengaging the stator core surface and in part defining a recessed channelradially outward relative to the stator core surface, said spray ringoverlying said channel and engaging the inner housing surface adjacentsaid channel, such that the inner housing surface and the spray ringcooperatively define a coolant-directing conduit that extendscircumferentially around at least substantially half of thecircumference of the stator core, said coolant-directing conduitconfigured to direct coolant to the at least one orifice.
 2. The motoras claimed in claim 1, further comprising: a stator-cooling passageextending along the stator core surface, with the passage beingconfigured to receive coolant flow so as to remove heat from the statorcore during operation of the motor, said coolant-directing conduitextending between and fluidly interconnecting the stator-cooling passageand the at least one orifice.
 3. The motor as claimed in claim 2, saidinner housing surface cooperating with the stator core surface to definethe stator-cooling passage.
 4. The motor as claimed in claim 1, saidstator core including opposite first and second ends spaced along theaxis, said windings including end turns positioned adjacent the firstend of the stator core, said spray ring configured to direct coolantonto the end turns.
 5. The motor as claimed in claim 4, said at leastone orifice configured to direct coolant generally radially onto the endturns.
 6. The motor as claimed in claim 5, said spray ring at leastsubstantially circumscribing the end turns, said at least one orificeconfigured to direct coolant generally radially inwardly onto the endturns.
 7. The motor as claimed in claim 4, said windings includingadditional end turns positioned at the second end of the stator core;and a second spray ring extending circumferentially relative to the axisand defining at least one second orifice configured to direct coolant onthe additional end turns.
 8. The motor as claimed in claim 1, said sprayring defining a plurality of said orifices, said orifices beingarcuately spaced apart.
 9. The motor as claimed in claim 8, said sprayring presenting first and second arcuately spaced apart ends defining agap therebetween, said spray ring presenting a middle spacedcircumferentially equally from each of said ends, such that a firstspray ring side extends from the first end to the middle and a secondspray ring side extends from the second end to the middle, a pluralityof said orifices being defined in said first spray ring side, adjacentones of said orifices defined in said first spray ring side defining anorifice spacing therebetween, said orifice spacing progressivelydecreasing for at least some of said adjacent ones of the orificesdefined in the first spray ring side in a direction moving away from thefirst end and toward the middle.
 10. The motor as claimed in claim 9, atleast some of said orifices being variably configured so as to optimizedirection of coolant on the stator.
 11. The motor as claimed in claim 1,said spray ring presenting first and second arcuately spaced apart endsdefining a gap therebetween, said spray ring being resilientlydeflectable, said motor further comprising a ring deflector operable toselectively deflect the spray ring and thereby expand or contract thegap, said ring deflector comprising a wedge fitted in the gap, saidwedge being adjustably positionable in a generally radial direction,said wedge including a pair of tapered faces engaging corresponding onesof the ends of the spray ring, such that generally radial shifting ofthe wedge deflects the spray ring and results in corresponding expansionor contraction of the gap.
 12. The motor as claimed in claim 1, saidspray ring presenting first and second arcuately spaced apart endsdefining a gap therebetween, said spray ring being resilientlydeflectable, said motor further comprising a ring deflector operable toselectively deflect the spray ring and thereby expand or contract thegap, said ring deflector comprising a plate received at least in partwithin the gap and engaging at least one end of the spray ring, saidring deflector further comprising a screw and a threadablyinterconnected nut, said plate being shiftable along the screw, said nutpresenting an outer rounded surface that engages the plate, withrelative rotation of the screw and nut causing shifting of the platealong the screw and thereby deflection of the spray ring.
 13. A motorconfigured to be cooled with a coolant, said motor comprising: a rotorrotatable about an axis; a stator including a stator core and windingswound about the stator core; a spray ring extending circumferentiallyrelative to the axis, said spray ring defining a plurality of orificesconfigured to direct coolant on the stator, said spray ring presentingfirst and second arcuately spaced apart ends defining a gaptherebetween, said spray ring presenting a middle spacedcircumferentially equally from each of said ends, such that a firstspray ring side extends from the first end to the middle and a secondspray ring side extends from the second end to the middle, a pluralityof said orifices being defined in said first spray ring side, adjacentones of said orifices defined in said first spray ring side defining anorifice spacing therebetween, said orifice spacing progressivelydecreasing for at least some of said adjacent ones of the orificesdefined in the first spray ring side in a direction moving away from thefirst end and toward the middle.
 14. The motor as claimed in claim 13,said motor further comprising a housing enclosing at least a portion ofthe stator, said housing including an inner housing surface, said sprayring and said inner housing surface cooperatively defining acoolant-directing conduit that extends circumferentially around at leastsubstantially half of a circumference of the stator core, saidcoolant-directing conduit configured to direct coolant to the pluralityof orifices.
 15. The motor as claimed in claim 14, said stator corepresenting an outer circumferential stator core surface, said motorfurther comprising a stator-cooling passage extending along the statorcore surface, with the passage being configured to receive coolant flowso as to remove heat from the stator core during operation of the motor,said coolant-directing conduit extending between and fluidlyinterconnecting the stator-cooling passage and the plurality oforifices.
 16. The motor as claimed in claim 13, said stator coreincluding opposite first and second ends spaced along the axis, saidwindings including end turns positioned adjacent the first end of thestator core, said spray ring configured to direct coolant onto the endturns.
 17. The motor as claimed in claim 16, at least some of saidorifices configured to direct coolant generally radially onto the endturns.
 18. The motor as claimed in claim 17, said spray ring at leastsubstantially circumscribing the end turns, said at least some of saidorifices configured to direct coolant generally radially inwardly ontothe end turns.
 19. The motor as claimed in claim 16, said windingsincluding additional end turns positioned at the second end of thestator core; and a second spray ring extending circumferentiallyrelative to the axis and defining at least one second orifice configuredto direct coolant on the additional end turns, said second spray ringpresenting first and second arcuately spaced apart second ends defininga second gap therebetween.
 20. The motor as claimed in claim 13, atleast some of said orifices being variably configured so as to optimizedirection of coolant on the stator.
 21. The motor as claimed in claim13, said spray ring being resiliently deflectable, said motor furthercomprising a ring deflector operable to selectively deflect the sprayring and thereby expand or contract the gap, said ring deflectorcomprising a wedge fitted in the gap, said wedge being adjustablypositionable in a generally radial direction, said wedge including apair of tapered faces engaging corresponding ones of the ends of thespray ring, such that generally radial shifting of the wedge deflectsthe spray ring and results in corresponding expansion or contraction ofthe gap.
 22. The motor as claimed in claim 13, said spray ring beingresiliently deflectable, said motor further comprising a ring deflectoroperable to selectively deflect the spray ring and thereby expand orcontract the gap, said ring deflector comprising a plate received atleast in part within the gap and engaging at least one end of the sprayring, said ring deflector further comprising a screw and a threadablyinterconnected nut, said plate being shiftable along the screw, said nutpresenting an outer rounded surface that engages the plate, withrelative rotation of the screw and nut causing shifting of the platealong the screw and thereby deflection of the spray ring.
 23. A motorconfigured to be cooled with a coolant, said motor comprising: a rotorrotatable about an axis; a stator including a stator core and windingswound about the stator core; a resiliently deflectable spray ringextending circumferentially relative to the axis, said spray ringdefining at least one orifice configured to direct coolant on thestator, said spray ring presenting first and second arcuately spacedapart ends defining a gap therebetween; and a ring deflector operable toselectively deflect the spray ring and thereby expand or contract thegap, said ring deflector comprising a wedge fitted in the gap, saidwedge being adjustably positionable in a generally radial direction,said wedge including a pair of tapered faces engaging corresponding onesof the ends of the spray ring, such that generally radial shifting ofthe wedge deflects the spray ring and results in corresponding expansionor contraction of the gap.
 24. The motor as claimed in claim 23, saidring deflector further comprising a threaded fastener that extendsgenerally radially, said fastener threadably engaging the wedge, withrotation of the fastener resulting in the generally radial shifting ofthe wedge.